This invention relates generally to control or adjustment of window coverings, and more particularly to ease and efficiency of window covering height adjustment. Such coverings are referred to as shades, and may be formed by pleats of a single piece of material, or by other configuration.
There is need for improvements in adjustability of such coverings or shades, as for example where the effective window covering height of the shade is to be adjusted. In the past, pleated shades were suspended by their own material, i.e. were allowed to hang, causing the weight of the shade to expand the pleats. It was then difficult to accurately adjust shade height, since over time the shade weight could expand the pleats, changing the overall height of the shade. Such pleated shades typically consisted of paper.
It is a major object of the invention to provide an easily adjustable means allowing shade height adjustment, and where only a minimum number of shade supporting lines are required.
Basically, the improvement comprises
a) upper support structure at or proximate the shade top,
b) at least one substantially vertically elongated shade support line extending downwardly from said upper support structure,
c) shade lower support structure at or proximate the shade bottom,
and shade adjustment includes:
d) elevating or lowering the shade lower support structure relative to the one or more support lines,
e) and effectively securing the shade lower support structure at a selected height position relative to the line length,
f) said securing including effecting attachment of the line to a fixed support relative to which the shade lower support structure is raised or lowered,
g) whereby the height of the shade bottom can be quickly manually adjusted by adjustment of the height of the shade lower support structure.
In one example the attachment is effected by adjustable wrapping of the line about a rotary drum; and in another example, the line is attached or anchored to a part of the window frame. In that event, the invention contemplates providing a clip supporting the lower support structure, and adjusting the clip along the anchored line to clip to the line at a selected position at which the lower support structure is to be supported.
As will appear, the shade is typically provided in the form of a sequence of pleats, and the line or lines is or are located adjacent such pleats.
Another object includes provision for weight of the lowermost extent of the shade to be carried by the shade lower support structure as that lower support structure is elevated to shorten the height of the shade. As the shade lower support structure is adjusted upwardly, the line below that support structure is typically wound automatically by a fixed position drum or rotor relative to which the lowermost support structure travels up or down.
A further object is to provide for encasing the fixed position drum or rotor in a housing, and securing that housing on window frame structure.
Another object is to employ multiple lines to support the shade lowermost support structure, such lines transferring loading to the line wound on the drum.
A further object is to provide a spring associated with the drum, and acting to urge the drum in a rotary direction to wind the line.
Yet another object is to provide a housing upper opening to pass the line for winding on the drum.
An additional object is to provide a manipulable brake in association with the housing to brake rotation of the drum or travel of the line, in shade adjusted position, and alternatively to allow rotation of the drum or travel of the line for winding or unwinding as shade height is adjusted. Safety is enhanced.